Radiator won’t work for sure, we already know that. K-member is obviously not going to work stock but it can be cut/boxed/modified. I suggested a BMR tubular turbo k-member for simplicity, weight savings and downpipe clearance. Automatics are easy on rears, I see the 8.8 lasting for a while with the power no problem.
Nothing is hidden here, it’s all fabrication and the parts are already there. I guarantee you that he can stay within budget if not beat it.