Jag XK 4.2 - advice

Hey everyone.

so new to the whole jag forum. Actually BMW M car guy - but helping a good friend with revitalising his Jag XK 4.2 (2007).

It's a one owner LHD car from new. with a lot of miles!

Anyway we're looking to bring it back to life... we have engine issues.

1. Firstly are there any Scotland based outfits who are familiar with XKs?
2. And if not who would you recommend if the car was located near London.

I suspect we may need a full engine rebuild. But whatever we do we want to update the power significantly (while keeping reliability and drivability.

Alternatively we would consider a 5.0 engine swap (new or low mileage - with history fully tracked).

Based on these options - what is possible? switching engines from a 4.2 to a 5.0 litre - is this even possible? And if it is has anyone done it, and post swap were there any issues?

And who would be good to carry this work out? Time frame and cost?

Additional questions:
3. Has anyone done a manual transmission swap on XK? If not, is it possible?
4. Can you recommend revised suspension all round - not necessarily want to change the feel - but we want it driving like new again - so question is do we upgrade to something else? OR just get OEM parts again / Or do we swap to XKR arms/suspension etc.
5. Carbon Ceramics - is this possible? has anyone done it - and what brand?
6. Any recommendations for body work - if we wanted to refresh the front grill fascia / with the refreshed XK front grill bumper - is this a straight swap? Or are there alternative grill options for a 2008 model.
7. Interior - any reupholsters that might be recommended
 

And in case you're wondering why not just buy a nearly new XK - its sentimental value - owned for 20 years - we ideally want to bring it back to life for the next 20 years.

This will all be documented - we'd like to get everything done and complete with 12 months. But we will only share the entire process once we've completed.