I have a government model 70series with a cylinder and slide drop in trigger job but i want a extended safety and was wondering how I would do this I know how to take out the safety and put it back in but how do I fit the new safety?

Did you install the new one yet? Did it pass ALL the safety checks? Pulling the trigger, safety ON with empty chamber is just one test. Any fitting/filing/grinding should be done by a qualified gunsmith. About all I can say is if you install it, as is, ensure it works properly before firing the first shot (starting with one round in the magazine),until you know all is well.

I haven't installed or even bought the new safety yet, I have only removed and installed the old safety which was very easy.  any tips for fitting a new safety?

Jerry,
If you really want to work on your own 1911, then I would strongly suggest getting Jerry Kuhnhousen's(sp?) 2 books on the 1911.  The first one covers repairs and basics, the second covers any kind of modification you could ever want to make to the gun.  These books also contain almost a complete set of dimensioned drawings of most of the major 1911 parts, the slide and frame with locations of ALL important holes in the frame.  

Most 'smiths will install any extended safety for about $40.  If you don't understand exactly what all the bits and pieces are doing inside a 1911, let an experienced 'smith do it.

(edited 'cuz I can't spell, I have really thick fingers, and my mom dresses me funny.)

Here's a second vote for the Jerry Kuhnhausen books.

I have a complete machine shop at the house, but I do not consider myself to be an experienced gunsmith - merely an amatuer.

I have fitted dozens of safeties, grip safeties and slide stops on 1911s I've owned over time.  Not only do you need to understand how the mating surfaces on the internal portion of the safety stop the action from working, but a custom fit safety should have a certain "feel".  It should take more than casual pressure to release and when it releases it should smartly snap to the off position ... same for the transition from off to on.

It takes practice to get it right.

If you want to do it yourself get the Jerry K book, if you don't want to experiment on your own gun and want the snappy feel have a gunsmith do it and be specific that you want it to feel that way.

Typically the first few safeties that one fits turn out a little on the mushy side.

Just my .02, best of luck and enjoy the 1911 it's a classic design that will never be outdated.

Ryan

I didn't add this above because it's slightly OT.

I thought of one more piece of guidance I could give.  I've been all through the different safeties the swenies, the browns, the kings, the cheapy brownells, etc.  

You mentioned that you have yet to purchase your safety.  You also mentioned "extended".  In my personal experience the "extended" or lengthened safeties are worthless.  The right safeties are the "wide" competition type like the brown, sweenie, and king.  If you are shooting any kind of competition you should go ahead and learn the high grip with the thumb remaining up over the safety and the supporting hand palm against the side of the grip, fingers wrapping around over the dominant hand fingers.

Some folks may sell this grip off as an "IPSC" thing or whatever, but it really does improve control.  Afterall better control means better sight picture ergo better "hits" ... on paper and in the real world, better "hits" count.

IMHO

Ryan