I cant say for that particular brand of seat but I put two bucket seats from a 2008 Scion TC (the car, not the box) in my car, it took about four hours to pull my buckets out, set those in, mark them out, level them up and bolt them in. The best piece of advice I can give you is to just keep looking toward the car, through the windshield, to ensure that the seats are level throughout the installation.
How do you like those Scion seats? Do they have a flat frame that will fit to our seat brackets? As for the Kirkey's, or any other aftermarket seat, the best bet is to get brackets that fit our floors first, then make an intermediate bracket to tie the seat to the stock brackets, if you need one. I spent 3 years trying to get Honda seats to fit before putting them to the curb...they just never would set right...
About those Scion seats Absolutely love them, I have the non electrical with lumbar support and recline. The frame of the seats are flat, just about 22inches wide or so, and have an extra mounting tab on the back corner (closest to transmission/driveshaft tunnel) that tab allows you to bolt it directly to the side of the tunnel. Unlike the Maverick buckets these seats don't use studs as they have bolt holes in the frames so I just used 8 9/16's bolts with wide flat washers on the heads and lockwashers as an extra precaution. They have plenty of slide to them, moving from nearly 6in from the steering wheel all the way to the back seat. Picked em up from a junkyard for 100 for the pair too.
i have kirkeys in my mav. i custom fabed brackets for them out of 3/4" square tubing. they are not adjustable. i have been thinking of geting some universal seat adjusters from summit and adapting them to my brackets. i have also installed the kirkeys in a 5.0 mustang. on that car i took the stock sliders of the mustang seats and used long bolts to bolt the kirkey seat on with. so if you have the stock mav bucket seat sliders then you should be able to easly mount them. if not then you need to fabricate or have brackets fabricated.