Looking for a Hilgen Pacesetter model R2521D schematic

[Gblekas1]

I have a buddy’s amp here for a cap job but it appears to have a bunch of mods done to it but without a schematic it’s tough to tell for sure.
The amp sounds good after plate resistor replacements and the cap job but the tremolo is thumping and the trem tube has triodes jumpered and a 12AY7 for that.

Anyway, thanks for looking either way