Innis & Gunn Rum Cask (add rum?)

I'm working on creating an I&G Rum Cask clone. I've started with a strong scotch ale recipe that I think will be close.

Should I add a little rum and oak cubes or should I just add a little rum that has been oak aged?

I was going to add rum (to taste) and oak cubes for a week or so. But I wonder if a good oak aged rum would get me the same result with less trouble?

Just had my first I & G rum cask. I love it! Gonna try to do something similar.

Figured I would throw this in here instead of making a new thread. I pieced together some bits and pieces from around the internet, and brewed up this recipe last weekend, hoping it will hit the I&G Rum Cask pretty closely (it tasted amazing going into the fermenter).

Innis and Gunnish - Rum Cask

Recipe Type: All Grain
Yeast: Wyeast Scottish Ale
Yeast Starter: Yes
Batch Size (Gallons): 5.0
Original Gravity: 1.077 (est)
Final Gravity: 1.020 (est)
IBU: 20.5
Est ABV: 7.5%
Boiling Time (Minutes): 60
Color: 17.5
Primary Fermentation (# of Days & Temp): 4 @ 67
Secondary Fermentation (planned): 7-14 on 2 oz rum soaked oak chips

11# Maris Otter
1# Victory Malt
1# Munich Malt
1# Crystal 60L
2.4oz Roasted Barley
1.6oz Chocolate Malt

0.75oz East Kent Goldings (60 min)
0.75oz East Kent Goldings (30 min)
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We started soaking the oak chips in Captain Morgans Private Stock a few days before brew day, and they smell great. Methinks this is going to be delicious...