Hi
maybe i could help. I am no super big contractor with big showroom.
1st - measure both your sink and hob. Most likely they are of different size.
2. most of the time the hob hole is bigger than sink hole.
3. what kind of surface is your kitchen top - solid top, granite or postform wood.
4. water piping re- works has to be done
5. gas piping has to be done, r u using pub gas or blue can gas.
6. Cutting of the kitchen surface has to be done provided it fits or can be cut to fit.
7. you need to find a sink that will fit your hob - any size bigger will help.
8. install the existing tap
how old is your kitchen ?
my advise is
1. change the top to a new soild top. about S$80.00 to S$90.00 per foot with back splash
2. this way you can reuse your existing sink and Hob and tap.
3. just need to re-work the sink and gas piping provided there are space for access within your kitchen cabinet structure.
email me at wahliow8@gmail.com for an onsite look. no obligations. cheers.