Heathkit HDOS source listings

Hello all, I recently acquired a 4-volume set of Heathkit HDOS source listings. They are in assembly langage, printed out on May 16th, 1980. They have nicely printed cover pages from Heathkit, and the rest appear to be photocopies of greenbar paper listings. I haven't examined them completely, but they appear to be intact, readable, and complete. The command processor and BASIC interpreter are definitely there, and there is a lot more as well... I'll post more details if anyone is interested. Also, I don't know if these are archived anywhere. If not, is there interest in getting these scanned and posted? If so, I'll move it to the top of the list. Bear in mind it's at least a 6" high stack, double-side printed, so "top of the stack" may still take a while to do... :-) I found some comments by a "J.G. Letwin". Perchance the same Letwin of OS/2 fame? Thanks, Rich B.