Hi all !!! finally got a title for my 77
need a lot of help

been into boats for the past 20yrs

but have always wanted a sq

just got me a 77 stepside and need a TON of help LOL ..
looking to build a pro street truck

plans
drop bed 3in level with truck cab
move springs inside frame
tubbed for 18in tires
TT ls 5.3 or 6.0 ,,,,,,, OR 540cid ????
trans ?????????????????
shortend 9" ....springs or 4 link ?????
tires 29 x 18.5
will be used for car/truck meets and to tow my jet boat