dodge durango freeze out plug

I have a 98 Dodge Durango SLT with the V8. The freeze out plug on the
right side of the block started leaking and over time has gotten worse
i've been pouring water in it by the gallon. I have to get it fixed by
winter so I took it to the garage at first the guy thought it would take
only a few hours 1 to 5 to fix. After he started he found he had to unbolt
the engine mount, remove some type of braket that was in that area.. jack
up the engine. still not enough room so he called and said he was 6 hours
into the work but it would take longer as he would have to Partally
disassemble the right side wheel and diferencial in order to lower the
motor mount in order to get enough room to put the plug in. by my
calculations this will prob be in the 10 to 15 hour range. does anyone
know if this sounds right or am i getting hosed. from my view it looks
like about $700 labor to replace a $5 part..