Look, there are a few types of crossfire people.
Most all buy the car for it's polarizing looks. I love how it looks. As most of us do. Then there are the guys, who go to all the trouble of putting the MB badging on the Crossfire. Why, I don't know. Yes It's more Mercedes then Chrysler. But if you want to show everyone that you own a MB, then buy a MB. Then there are the folks who buy the Crossfire for it's great handling characteristics for the amount of money you spend.
The Crossfire was designed to bookend the Corvette along with the Viper. The idea is, you could buy a Viper that was better then the Vette for more money. Or buy the Crossfire for a little less money, but still "hang" with the Vettes. It was a good idea. I'm not sure they pulled it off. And it's a moot point as the Crossfire is discontinued.
Maybe I'm speaking out of turn when I would like to say for all of us. That the Crossfires character is about handling. Not the quarter mile. Even though those SRT-6's rip the quarter mile.
I guess you'd get a lot more respect for what you are doing if you at least try and keep the "character" of the car when you do your "ratrod"-ish build. How about a 340 six pack with an A-833? Like in the AAR Cudas? With some AAR type stickers on the side of the "AAR Crossfire". You do know someone has put a 5.7 Gen III Hemi in a Crossfire. So putting a "truck" 360 and the little 904 automatic is a little, um, out of character. Most of us would have died to have a 6spd SRT-6. And you want to put a 904 in it? Boring. How about an aluminum LS motor and a Vette transaxle? Still fairly light and well balanced.
I guess you could cheap out if you don't have a budget. Put the 360 in with the 904, yawn. It will still kill it in the quarter mile. But at the expense of a car that used to handle great.
What ever you decide to do, I'd love to see it. I'll just be disappointed. Because, like my beloved A-Bodies, which by the way, are the best handling muscle car, your crossfires soul(handling), will be ripped out in pursuit of quarter mile times.
The grandfather of the Crossfire? The Barracuda.
In Torque We Trust - 1967 Plymouth Barracuda Formula S - YouTube