please remember towing capacity means nothing in this application. Payload is your limiting factor. older half tons will have significantly less payload than modern ones nut should still be enough if you travel light.
payload - weight of all accessories on truck (including your 100 lbs of hitch) - weight of people in truck - tongue weight of the trailer. you still want a positive number (the more left the better especially with an older vehicle)
shoot for 13 percent tongue weight. as an example of my setup
my 2016 f150 has 1950 lbs payload (very good for a half ton)
1950
- 90 (hitch)
-500 (people)
-400 (gear in bed)
= 960 remaining
960/0.13 = 7385 trailer fully loaded.
my camper is only around 5500 fully loaded and my truck handles it nicely. wouldn't want much more than I have back there. My last tow vehicle with my old camper was also in the numbers but much closer to the limits. Not nearly as nice a drive.
