Where in the Great White North do you live. In my parts book, the only snap ring listed is the forward clutch retainer snap ring and it is .060" thick.
Thanks for the information transman! I am in the London Ontario
I was digging around more on some parts websites, and there appears to be different part numbers for the reverse drums. I found D12556A for reverse drum, no washer under the support snap ring, and D12556B for washer under the support snap ring. I am guessing they used both styles, and I might have the D12556A version. Just not sure why I have the witness marks.
I did end up reaching out to some of the converter companies you mentioned to me in another thread. I ended up with an SMR XPL-25 for my build, so thanks for that suggestion.