AES/ AE-1 modifications

I have been through several preamps in the last year and a half. Always looking for that (this is it) preamp. I decided to pick up this AE-1 until I could figure out what the heck I wanted. I have spent about 2 months with this pre. I have found that I like the design of the AES a lot. Dual volume controls, point to point wiring. And tube sockets screwed into the top plate for stable tube rolling. And I like the tube exposed design.
The unit sounds pretty good. My problem is that I listen to classic rock vinyl. So some of the pre's that I had tried were too analytical. Classic rock and analytical don't go good together. The AES is smooth and warm, just what I was looking for.
But, the bass could use a little tightening up and there could stand to be a little more spaciousness.
So I am asking for some assistance in tweaking this thing. I have done some research on it and I believe it uses paper caps. I could switch them to oil filled caps. How much of a difference will that make? What else should I be looking to do to this pre?
Thanks, Scott
Or, better yet. Suggest someone who could perform a full blown out modification to this piece.
Scottht, you will find that changing out the stock caps will make a dramatic difference in the sound. I have a Cary SLP98 that had the upgraded paper-in-oil caps from Cary and the sound was thick, somewhat slow, bloated.

After reading many posts here and on AA about the caps that Cary uses and their not so superior sound quality, I knew they had to go. Replaced the pio caps with Hovland Musicaps and the SLP98 has never sounded better. I called and talked to Kirk at Cary about the caps----short story is that he uses Hovlands in his own personal SLP98, and Cary doesnt even sell them as a upgrade.

Change those caps out and you will be amazed at what you will hearing. Diamond in the rough. Let us know of your progress.

I had talked to Billy at AES and he want's me to buy oil caps from him. Should I look elsewhere. Should I just consider certain caps?
Where can I get these Hovland caps?
Scottht, you can buy these from Parts Connexion . Both the AE-1 and the SLP98 are close to identical in design, so you should have sucess with them like I have.

The Hovland caps that I see there are paper andfoil polypropelene, Are these the ones that you are talking about?
Thanks for the info
Scottht, yes these are the film-in-foil coupling is the sku from Parts Connexion "HOVLAND- sku #55271 2.0uf @ 400v, 0.98" D x 3.00" L $24.65 each". Call and talk to Chris Johnson he can answer all your questions. Great service and shipped out the next day.