73-87 guys with Crossmember mods and/or Frame Z's.....

[74Chevy74]

Ok guys I have a few questions.... I've got a 74 SWB 1/2 I want to lay pinch weld on so here's some questions I have... I was thinking if I can to do a 1.5" crossmember section if I have the room, and maybe a 2" Z, I'm also going to take the 1.5" off the bottom of the frame under the cab, I know all trucks are different so I'll just have to check as I go. The one thing I'm really trying to avoid is raising the tranny tunnel which I know is not possible, I just want to be able to run stock carpet, do you think if it is raised an 1" or 2 It will still fit? I plan on running 20's with a 40 series.... any input would help! Thanks.