'79 K20 Cross member spacers?

[zac]

I bought a '79 K20 Camper Special last week to be a work truck. Good body, needed mechanicals. 350sb/TH400/203/14 bolt(big)/10bolt. Sammy the Squirrel had done some work on it, too much to list. Broken trans case, only two bolts holding trans to engine, etc. I'm installing a new trans and a good 203. The guy I bought them from mentioned his truck had spacers under the trans/t-case crossmember that dropped it below the frame a half inch or so. I have seen them on other trucks, but mine doesn't have them. The bolts that were holding the crossmember on were different sizes and not even tightened all the way. I suspect Sammy may have left them out, but I don't know. Should my truck have them? Can I get them mail-order? How about making some out of steel tubing (I'd hate to use washers)? How long are they? Grade 5 or 8 bolts?

Thanks in advance.