CEN,
I replaced the servos on my MT2 with the Hitec HS-325 as the throttle servo and the 645MG as the steering servo. What metal horns do you suggest? I ordered the OFNA
Aluminum CNC servo arm (purple)-10732. I think the holes are too close together and the one on the end is to big. I read this article and wanted to upgrade; http://www.rcnitro.com/rn/articles/superShop_3.asp

We have always recommended using the stock servo horns that come with the servos. They are specifically made for the servo purchased. Holes can be redrilled to the desired size.

CEN Racing

I replaced my servos with Hitech also except I went with 645mg all the way... I used the ofna purple servo horn.. it is a little loose on the ends as you said.. I used a homemade adaptor rigged from du-bro airplane hardware... I chose to leave the stock horns that came with the truck on the steering for 2 reasons... 1.. They fit with no modification......
2. I can't see them, so it's not important how they look...

part of the fun is being creative with the trucks.. experiment with linkages and see what works for you.. just be careful of the cylinder head... I tried to mount the linkage on the bottom,but it didn't work well...

Cenracer1,
Thanks, I will give it a try.