Sounds good Dave,
Probably best to wait until you get a dry'ish spell of warmer weather. I say warmer what I mean is above freezing.
Your best bet is to skim the grass off and stack it, upside down, in an unused area for that to compost down, and off you go!!
You got a good deal there I reckon! I would think that the friend would not be averse to the occasional fresh veg either as a bonus!!
O B