Well the original transistors were BDV65 and BDV64 and there was no spacers. However the amp was worked on by a previous tech and he deemed it non-repairable, which of course is not the case. TIP 142 and TIP 147 are suitable replacements, I'm just confused as to if that spacer was there previously or if now with the transistor sub it may be required. I'll check the schematic to see if I can tell if the collector was originally grounded.