Re: Bags on the rear
Usually, if you have to ask if it's hard, then it probably is, but then again, it really depends on which route you take to get it done.
I'll second the recommendation to just use air shocks to help with a load. If you were to bag the rear (like a link suspension), then you would have no "fall back plan" if you were carrying a load and had any kind of failure. Atleast with air shocks just bolted in place of the stock shocks, you could still get around with a sudden air leak.