2005 2.7-Rear Main Seal Replacement Q?

so i've lost my workspace for the truck. the clutch is getting a little week so i asked a local shop what they would charge to replace the clutch, slave cylinder and rear main. he said $450 for the clutch and slave, but the rear main would add another $300. i've replaced the rear main on a front wheel drive car before, is there something about the rear main design with this truck that would add another $300 with the transmission already off? he mentioned something about a one piece or 2 piece design. i have all the parts also, that is why the quote was so cheap. any thoughts on the extra $300 for just changing out the rear main?

 

If its anything like the 3rz which I'm sure it is I don't see why it would cost so much with the trans already removed to do a clutch. I just did my clutch and rear main on my 3rz yesterday, once flywheel is off its as simple as popping a few bolts out of a plate, pull the plate off pop out old seal install new seal add some silicone and slap it back together. This is on a one piece seal design, 2 piece seal requires dropping pan but I don't know of many vehicles that use a 2 piece seal sense the late 80s early 90s.