Here's what I would do for a 1-gallon IPA. I'd only bother with a 15-minute boil, since it's an extract batch. But then I'd hop stand/whirlpool for 60-90 minutes after the boil. IBU's will end up measuring in the 90-100 IBU range, but probably only taste like 60-70 IBU's.
Title: 1-Gallon IPA
Brew Method: Extract
Style Name: American IPA
Boil Time: 15 min
Batch Size: 1 gallons (fermentor volume)
Boil Size: 1.5 gallons
Boil Gravity: 1.043
Efficiency: 35% (steeping grains only)
No Chill: 10 minute extended hop boil time
STATS:
Original Gravity: 1.064
Final Gravity: 1.018
ABV (standard): 6.09%
IBU (tinseth): 292.38
SRM (morey): 6.61
FERMENTABLES:
1.5 lb - Dry Malt Extract - Extra Light (92.3%)
STEEPING GRAINS:
2 oz - American - Caramel / Crystal 40L (7.7%)
HOPS:
0.2 oz - Apollo, Type: Pellet, AA: 18, Use: Boil for 15 min, IBU: 50.65
0.5 oz - Apollo, Type: Pellet, AA: 18, Use: Boil for 0 min, IBU: 66.05
0.7 oz - Citra, Type: Pellet, AA: 14.8, Use: Boil for 0 min, IBU: 76.03
0.7 oz - Meridian, Type: Pellet, AA: 6.7, Use: Boil for 0 min, IBU: 34.42
0.7 oz - Nelson Sauvin, Type: Pellet, AA: 12.7, Use: Boil for 0 min, IBU: 65.24
0.3 oz - Apollo, Type: Pellet, AA: 18, Use: Dry Hop for 7 days
0.3 oz - Citra, Type: Pellet, AA: 14.8, Use: Dry Hop for 7 days
0.3 oz - Meridian, Type: Pellet, AA: 6.7, Use: Dry Hop for 7 days
0.3 oz - Nelson Sauvin, Type: Pellet, AA: 12.7, Use: Dry Hop for 7 days
YEAST:
Fermentis / Safale - American Ale Yeast US-05