I ended up TIG(ing) the washers in place by edge welding. I used 2 pcs of 1/4 x 1 x 6 in. AL strips on either side of the two parts as aheat sink with the AL strips locally flush with the OD of the thrust washer and clamped in a bench vise. THe shims were slightly larger in OD as compared to the thrust washers and melting the edge of the shims also served as the filler material. I set the Lincoln welder to the lowest of the three heat ranges and was very apprehensive at first with the ammount of foot petal to use. By the time I was welding on the 2nd thrust washer, I had the foot petal at max for 5 to 10+ seconds. Initially, I only intended to tack on the perimeter in a few places. I ended up with stitch welding the entire perimeter. Each stitch weld being about 1/8 in. long, with about 80% of the welds on the perimeter remaining after dressing the welds for flatness (and cutting thru a few). After each weld I had to reposition the AL heat sinks relative to the circumferance of the part - frequently dressing the prior weld to maintain a good clamp between the washer and the shim. Took me just under an hour (if I had cut two AL discs the same size as the thrust washer, the welding would have been much faster but I'm not certain if they would have worked as well as heat sinks. Once I got home (I did the welding at my employers protoshop while the shop employee's were on their lunch break) I lightly lapped the surface with some very course lapping compound and test fitted the shims. Spec for the Triumph transmission (car, GT6) laygear cluster is 0.007 to 0.013 end play - mine is now at .006. A bit more lapping and it will be done. I'm stoked, I've never tried to do such delicate welding. In my opinion, the success was all in the AL strips used as heat sinks.