[Michael C Henry]

The Truck engines that I remember had different cranks. Getting hipo stuff for older FE truck is difficult.On the later small block pushrod truck engines had a different firing order than the engines in the cars . The cam would dictate that . And the 390 has the same stroke as the 427 but bores differ making the large valve heads of a 427 a no go.and the 427 is an almost race ready prepaired engine clearenced, oiling system modifications, etc.
In 60 Fords hot FE was a 360 hp 352. In 62 it was a 401 hp 390 in 62 it was a 410 hp 406. 63 it was a 425 hp 427 then the sideoiler, then in 68 they came up with the 428 to fill the gap between allout and streetable machines. With all the preperation involved with a 427 the 428 was also much less expensive . Picture the same blocks and start changing the bores and strokes but allways using the good parts.You can make a terror out of a 390 by evolving it into a 406 you're going to buy new pistins anyway.The truck heads arn't very racey either.
Everything has a trade off a 352 with 4" bore and a 3.5" stroke has less torque potential but higher rev potential than a 390-406 with a 3.78" stroke. The 390 is .050" bigger bore take that another .075" and you have 4.125" that is the bore for a 406 and a 428 take the 406 stroke it another .200" and you end up at 3.98" for a 428. 427 start out at 4.230" bore and its hard to get another block to go that large and end up with any cylinder walls left. Given that all the parts are the best available there is allways a trade off. short strokes give up torque for rpm potential. Bigger pistons are heavier and forged pistons are even heavier.Cheap to buy will end up expensive to build.How fast did you want to go?