various F150 truck forums mention the frame difference. But nobody links a source of the info… so like I said, google/internet confusion.
Example of part of a discussion from oilburners.net
"Diesel_brad said: ↑
Frame is no thicker than a 4x4 frame.
Has 4:10LS factory .
Only interior difference is the lightning seats and 120mph speedo.
Dark charcoal interior is from 87-93. the light opal gray is 94-97.
It is lowered 1" in front 2.5" in the rear and has slapper bar
Steering box has 17:1 ratio…not sure if any different from any other f-series
functional front air dam with fog lights
hmm, the lightning frame was thinker, 0.170 versus the 0.143 inch on the regular F150- and it had brace plates welded on the kick-up over the rear axle. this kept chassis flex to a mimimum and contributed to the gen 1’s amazing handling.
the lightning had a special gray interior, WITH fully adjustable sport seats with embroidered lightning logo and full xlt trim.
it was 1 inch lower in frt and 2.5 in rear with a slapper bar, and bigger frt and rear sway bars and monroe formula GP shocks
yes it has a quick ratio steering box, but im not sure of the measurements.
out of a brochure for the lightning, which i guess ford could be sued for if it was wrong. and that looks like a nice lightning, but there are some things i guess you didnt know about it, i do like the newer rims on it and where you put the lightning emblems on it"
Which seems to be clarified by a poster named tjc transport at the Ford Truck Enthusiasts Forums:
“250 and 350 frames are the same. 2 wheel drive and 4 wheel drive frames are different.
both 2 wheel and 4 wheel 250/350 frames are much heavier than the 150 frame.”
So it gets tricky to plan the factory interchange bolt ons (OEM plus) swap as you are trusting unconfirmed forum info and it isn’t actually answer the question of “it will fit and work properly” whether you have a specific frame or not.