how hard or easy is this to do?
Here is the parts breakdown
Replacement parts for WHIRLPOOL GEW9200LW0 | AppliancePartsPros.com
And this should help with the replacement, see page 4-10
https://secured.whirlpool.com/Service/SrvTechAdm.nsf/2cd44500d572193285256a45004fd9d6/cdce3c10dcb5382285256aa20064beaa/$FILE/Duetdry.pdf