Get the 525efi,s and order 496ho stickers (labels) remove the tags on the new 525,s and put the 496tags on them.. They wont know the difference

My opinion on the 496ho,s you will loose speed and gain reliability.
However it depends on what your looking for. But I'm betting your
like most of us here in the east you want speed!!!

Another option would be if you have the resources rebuild the engines you
have. There are quite a few custom engine builders here in the states
that could help you. Don't know if you have local ones in Germany.

You have 500hrs on the engines? Then there is some performance to gain by
rebuilding.

The trs drives are still a reliable unit up to 550 HP if your not having problems
now just leave them alone. ( just change drive fluid often). You have Borg Warner transmissions? Keep up on fluid Changes in them and make sure your running coolers.

Silent exhaust is getting popular here in the states also. I just got a ticket for being loud myself. There are many mufflers and silent exhaust available.

Silent but deadly sounds like trick

There are many people here on this board that will be glad to help
you..

Gerry

Please post more pics, those Cougars are nice, good luck: Matt

in the neyt 2 day would post more pics...
I hope that many poelple will answer my questins soon...
Greetz

could anyone help me,too??????

If I were as restricted as you, i would leave the TRS outrives alone. Check them for problems. For engines the 496HO sounds like your best option. It will be the most unaffected with silent exhaust too. I would just do the engine swap and keep your TRS. Are you planning to by new engines?