Batboard

What is the easiest way to convert an 800Mhz Maxtrac to use as a 900MHz repeater receiver from start to finish? Will an 800MHz Maxtrac have better sensitivity than a 900MHz Maxtrac? Are the Maxtracs narrowband capable? I'd imagine one could use a plain old D27 conventional version. I already have the Murata filters to change the bandpass. What do I do next?

Thanks,
Charles