Note: use typeset to find out what params are

Use this command:
diff -y <(od -An -v -tx1 -w1 file1) <(od -An -v -tx1 -w1 file2)
or: diff --suppress-common-lines -y <(od -Ax -v -tx1 -w1 file1) <(od -Ax -v -tx1 -w1 file2)

for 2 bytes at a time, offset:
diff -y <(od -An -v -j1 -tx2 -w1 file1) <(od -An -v -j1 -tx2 -w1 file2)

display:
od -Ax -w1 -v -tx1 file1

--
0x01-0x19: name of stunt, encoded as fixed-length ASCII string
--
Global settings

0x27: Rec: off is 0x00, auto is 0x01, on is 0x02; (defaults to 0xFF?)
0x28-0x29: 1st Take Bonus: encoded as two-byte unsigned integer
0x2C: (packed bits)
	76543210 <-- bit numbers
	-----bfg <-- represented values
	b: brakes on if true
	f: flaps down if true
	g: gear up if true

0x2E-0x2F: time of day
0x31: default cam (number minus 1)
0x32: weapon: none 0, gun 1, missile 2, bomb 3
0x33: max takes (changing from 99 also changes 0x27 to 2, 0x2E to 45)
0x34-0x35 (take penalty), 0x2A...?...0x2E (crash penalty) do strange things with 0x27 and 0x2E as well, setting it to 0x2 if it's previously 0xFF
0x3E: View: Pilot CP is 0x00, Pilot no CP is 0x01, Left side is 0x02, Right side is 0x03, Rear is 0x04, Bomb is 0x05, Spotter is 0x06

--
0x54: adding at least one event changes this from 0 to 1

--

Deleting prop #1 just removes lines 0x97 through 0xD6; no other lines change. Therefore, 0xD7 is first line for prop #2 (if prop 1 exists).

Conclusion: Every prop takes (16*5=80 bytes)
Conclusion: List of props is terminated by a 0 byte.

> diff -y <(od -Ax  -to1 -w1 -v 100000.SET) <(od -Ax  -to1 -w1 -v NOPROP1.SET) # useful for comparing prop 1 and prop 2


--
0x99: (packed bits)
	76543210 <-- bit numbers
	-ve-caw- <-- represented values (on if true)
	v: visibility (might not be right; looks like this is down in 0xCB)
	e: explodability
	c: collideability
	a: autozoom
	w: watch

0x9A: (packed bits)
	76543210 <-- bit numbers
	-----s-p <-- represented values (on if true)
	s: shadow
	p: placed

	
x99: collideability of prop 1 (x09 if on, x01 if off)

--
changing Prop #1 type alters values at offsets x9b and x9c

--
The offset for E/W position of prop 1 starts at 9d (instead of a5)

Changing N/S position of first prop results in the following changed values (in hexadecimal, offset by 1 byte into file); first byte is actually a good bit earlier at a1, other two are at a5 and a6:
offset: a1 a5 a6 a7 a8
099980: 00 00 00 fe ff 
099990: 00 00 00 ff ff 
099999: 00 66 e6 ff ff 
100000: 80 00 00 00 00
100001: 00 99 19 00 00
100002: 00 33 33 00 00
100003: 00 cc 4c 00 00
100004: 00 66 66 00 00
100005: 00 00 80 00 00
100006: 00 99 99 00 00
100007: 00 33 b3 00 00
100008: 00 cc cc 00 00
100009: 00 66 e6 00 00
100010: 00 00 00 01 00
100011: 00 99 19 01 00
100012: 00 33 33 01 00
100013: 00 cc 4c 01 00
100020: 00 00 00 02 00
100030: 00 00 00 03 00
100100: 00 00 00 0a 00


Positions can range between 0 and 200000 (decimal).

Singles digit of altitude is at a1 and a2, tens are at a3.
offset: a1 a2 a3 a4
alt00:  00 00 00 00
alt01:  67 e6 ff ff
alt02:  cd cc ff ff
alt03:  34 b3 ff ff
alt04:  9a 99 ff ff
alt05:  00 80 ff ff
alt06:  67 66 ff ff
alt07:  cd 4c ff ff
alt08:  34 33 ff ff
alt09:  9a 19 ff ff
alt10:  00 00 ff ff
alt11:  67 e6 ff ff

xA9,xAA: facing roll of prop 1
xAB,xAC: facing pitch of prop 1
xAD,xAE: facing yaw of prop 1

xB5,xB6: speed of prop 1

xCB: (packed bits)
	76543210 <-- bit numbers
	----lv-- <-- represented values 
	l: lock of prop 1 is on if true
	v: visibility of prop 1 off if true

Hide:
if it's on, xD6 and xDA have values of 031, and if it's off, values of 033

--
0xE1-0xEC: adding a single event changes these values

--

Used these commands:
diff -y --suppress-common-lines <(od -An -v -j1 -tx1 -w1 100000.SET) <(od -An -v -j1 -tx1 -w1 100001.SET)
diff -y --suppress-common-lines <(od -An -v -j1 -tx1 -w1 100002.SET) <(od -An -v -j1 -tx1 -w1 100003.SET)
diff -y --suppress-common-lines <(od -An -v -j1 -tx1 -w1 100000.SET) <(od -An -v -j1 -tx1 -w1 100003.SET)

--
xFF-x100: changing pitch of spotter plane