I have a Whitworth .375 H&H. Will a Timney Mauser trigger with the sliding safety fit a Whitworth? Thanks.

Yep The #301(FD M98FN) will fit the MKX, whitworth and most 98s.

How much "fitting" is required or is it pretty much a drop in? Also, how about the Bold Optima, any opinions there? Thanks.

Take out the old MKX adjustable trigger and stick in the Timney. There MIGHT be a touch of stock fitting(mostly if not all internal) to clear safety lever.

I placed a Bold on my wifes MKX. As a trigger it works great. However the design of the safety lever SUCKS!. The Bold lever WILL require (or at least the 3 I've delt with) significant wood removal. Then the lever will stick out and away from the side of the action.

I've had 3 Bolds on the two I kept I ended up cutting the knob off the lever. Heating and changing the angle of the lever bending over the tip and reattaching the knob. Probably shortening the lever 1/4" or more and moving it at least that much closer to the action. To me they just leave what to much space between the safety lever and action. Function of the trigger is great. I would be happy to use one of the Bolds If I had a shroud safety.

Mike,
I'll give you 10 bucks for the old trigger

Good feedback on the Bold, thanks. I have used Timney triggers with great success to date but was trying to get an idea if this was a job that I should attempt on my own or have a gunsmith undertake.

Mike as to metal work it is a simple swap. The wood might clear with no problem. If not it is usally removal to clear the lever. Buy it take off the odl install the new. If it fits great. If not and you don't feel comfortable removing wood then take it to someone.