Very nice choices! I want to hear that SLI80 after they break in! Where do you live and what speakers do you play? 
Are those original Genelex KT88s? Sweet! I ask because new production Electro Harmonix KT88s also have the black base cap like the later Genelex. But McIntosh did private label the original Genelex GEC-MOV KT88s back in the day. New Mac power tubes would be no advantage over your stock EHs.
Don't forget the coupling caps... 
Thanks~ I live in Crook County, Chicago, Illinois~ Running a pair of JBL L50, also some VR2's speakers, JBL L16 and a few other speakers~ Yes, original tubes and not cheap! I will see how it goes after I install of these new tubes then maybe do a few more upgrades to the amp. I also have a sweet sounding Jolida FX10 with some JJ tubes and the amp was modified by Rich Singerman out of Cali, that's next on the list for tube rolling and I believe it will be less costly too~ lol~ Thanks and Happy New Years
