hi all.. need 350 tbi advice

I bought 2 trucks. 1, 1981 3/4 ton bo lo 4x4 3/4 ton 4 bolt 350 engine, and a 305 tbi 1987 2 wheelie peely.. I am putting all the wiring from the

1987 into the 1981, pulling the 4 bolt 350 (propane powered all her life) with bo lo tranny and putting a 700R4, 1992 ,350 tbi in it. I know I know. BOOOO... I love carb, but wanted to try something new.. I have never put a tbi in a truck..let alone this big of a conversion.. The question I ask is.. what is the biggest cam I can put in the tbi before the computer goes brain dead..?.. I was told 2 sizes bigger than stock... but what was the stock cam in a 1992 2500 van 350 tbi ? Any help would be great.. thanx for your time.