The Sendero is just a Model 700 with the heavy barrel and synthetic stock.
As for the conversion, it can be done, but it sometimes take fiddling with the feeding.
This is critical with a push feed rifle. If a round is pushed into the chamber, but the bolt is pulled back before the extractor engages, the round can be left in the chamber. If the feed guides are not right, and the bolt is again moved forward, the bullet point of the round coming from the magazine can strike the primer of the round in the chamber. Problems will follow very shortly thereafter. In addition, work is needed to keep the short round from popping right out of the action when released from the magazine.
(This is the real reason Mauser went to "controlled feed" as soon as jacketed and pointed bullets came along, not the usual stuff about preventing jamming.)
In brief, changing calibers in the Remington 700 and other push feed rifles should be done by an experienced gunsmith and the job is not as easy as simply putting on a new barrel.
Frankly, I recommend trading the .30-'06 on a .308 and forgetting the conversion idea. It will be more satisfactory and probably a lot cheaper.
Jim