those temps arent too bad but if it was my own system i wouldnt leave the old paste on there. i would redo it.
95% isopropyl alcohol (available at your pharmacy or most stores in the medicine area) works like a charm. use a q-tip (cotton swab) dippin in it to rub off any old compound (it comes off very easy) then use the dry side of the q-tip to soak up the excess alcohol (but it does evaporate quick). then just wait a minute or two for it to evaporate and you are ready to apply fresh compound.
remember to do both the heatsink base and the chip top.